Combination
All applicants who are applying for a Class A CDL should be prepared to take the Combination test. This test covers information found in Section 6 of the Montana Commercial Driver License Manual. Section 6 provides the information needed to safely operate tractor-trailers, doubles, triples, and straight trucks with trailers. The test is made up of 20 multiple-choice questions, and applicants will have 20 minutes to correctly answer a minimum of 16 questions. The Combination test is not a replacement for the Double/Triple endorsement test.
Number of Question
Passing Score
1. The ____ trailer is the most likely to turn over if a driver takes a turn too quickly.
Explanation
When making a turn, be sure to steer gently and smoothly. Making a quick turn while pulling trailers is dangerous and can increase the risk of the last trailer rolling over.
2. Bobtail tractors are ____ to stop than tractors attached to full semitrailers.
Explanation
Bobtail tractors are tractors that are not attached to any semitrailers. When operating a bobtail, you should be aware that stopping can be difficult and that it will take a longer distance to come to a complete stop than a tractor attached to a loaded semitrailer.
3. What is a tractor protection valve?
Explanation
In a combination vehicle with air brakes, the tractor protection valve keeps air in the tractor or truck brake system in the event of the trailer breaking away or developing a leak.
4. To lower the risk of a rollover, you should:
Explanation
To lower the risk of a rollover, load your cargo as closely to the ground as possible. To further reduce this risk, take curves and corners slowly.
5. When connecting a converter dolly to a second or third trailer, the trailer height should be:
Explanation
When connecting a converter dolly to a second or third trailer, the trailer height should be correct. It should be slightly lower than the center of the fifth wheel.
6. A shut-off valve:
Explanation
Shut-off valves are used in air supply lines to control the passage of air from one trailer to another. The rear shut-off valve should always be closed to prevent air from leaving the braking system.
7. During a trip, which shut-off valves should be open?
Explanation